Various forms of fuel heaters heretofore have been provided to increase fuel efficiency operation of existing internal combustion engines utilizing liquid fuel. However, most of these previously known forms of heaters either provide too much heat to the fuel being heated or insufficient heat during various different periods of engine operation. Further, while some forms of fuel heaters include precise controls therefor whereby reasonably constant heating of fuel may be accomplished, these latter types of fuel heaters are relatively complex and incorporate heating controls which are subject to malfunction. Accordingly, a need exists for a simplified form of fuel heater capable of heating engine fuel to substantially the desired temperature during operation of the associated combustion engine under different climatic conditions.
Examples of previously known forms of fuel heaters, including some of the general structural and operational features of the instant invention, are disclosed in U.S. Pat. Nos. 1,168,111, 1,318,265, 2,231,525, 4,050,426, 4,218,999, 4,233,945 and 4,248,197.